Hello I am new to the world of Ipad and forums but seem to be a fast learner. According to Apple the Ipad battery usage is good for 10 hours. I did a little snooping to find out how to increase or maintain battery usage time. After the push mail turn off and the WiFi turn off if not using it I also tried the brightness. I have huge issues with my eyes and light to begin with so dialling down the brightness for me was a no brainer. I use my Ipad mainly for reading my IBooks of which I have over 600. Long story shortened I now get 13 hours and 40 minutes with 25% battery usage left! Wonder if that is a record?
(Posted this in hopes of helping someone else out).